While I still hand file a chain saw chain if I am running the saw,I have given up on my farm help. Now days I just have them change out the chain before they burn up the bar. After a reworking the HF sharpener it does a good job of sharpening the loose chains. The part that holds the chain needed the work. If I was doing it for customers it would up grade to something like the Oregon one. For the twenty or so chains a year I do the reworked Harbor Freight does ok. It's kind of like buying a Harbor Freight horizontal band saw. The are better units out there,but with some modifications they will work